= chelating aromatic nitrogen ligand, N = non-chelating or bridging ligand). The reaction and the product distribution can be controlled by adjusting the reaction stoichiometry. The reactivity of the new ruthenium complexes was tested in 1-hexene hydroformylation. The activity can be associated with the degree of stability of the complexes and the ruthenium-ligand interaction. Chelating or bridging nitrogen ligands suppresses the activity strongly compared with the bare ruthenium carbonyl chloride, while the decrease in activity is less pronounced with monodentate ligands. A plausible catalytic cycle is proposed and discussed in terms of ligand-ruthenium interactions. The reactivity of the ligands as well as the catalytic cycle was studied in detail using the computational DFT methods.

Carbonyl-containing ruthenium mono(bipyridines) are effective catalysts or catalyst precursors in processes such as the water-gas shift reaction. Ethylene glycol solutions provide versatile solvent systems for synthesizing the mono(bipyridines) from [Ru(CO)3Cl2]2 and 2,2‘-bipyridine. These starting compounds were used here in the preparation of three primary products, Ru(bpy)(CO)2Cl(C(O)OCH2CH2OH), Ru(bpy)(CO)2ClH, and [Ru(bpy)(CO)2Cl]2, which were formed consecutively and isolated by adjusting the reaction conditions. Reactions were studied by analyzing the solid products and monitoring the evolution of gases in each reaction step. Computational nonlocal density functional methods were applied to estimate the total reaction energies and to study isomerism of the compounds. Ethylene glycol solvent plays an active role in the synthesis reactions. It provides a reactive alkoxy group, -OCH2CH2OH, which is able to act as a nucleophile attacking the carbon of a Ru−CO group. The first product, Ru(bpy)(CO)2Cl(C(O)OCH2CH2OH), is formed under mild conditions at room temperature. The alkoxy carbonyl complex reacts further to Ru(bpy)(CO)2ClH and CO2 when heated. Formation of the hydride complex requires the presence of water. Ru(bpy)(CO)2ClH can be further converted to dimeric [Ru(bpy)(CO)2Cl]2. Ru(bpy)(CO)2Cl2 is a side product which is also obtained from [Ru(CO)3Cl2]2 and 2,2‘-bipyridine. Crystal data:  Ru(bpy)(CO)2Cl(C(O)OCH2CH2OH)·1/4(HOCH2CH2OH) (1), space group C2/c, cell constants a = 27.889(3) Å, b = 10.270(2) Å, c = 26.563(2) Å, β = 112.01(3)°, V = 7053.7(17) Å3, Z = 16; Ru(bpy)(CO)2ClH (2), P1̄, a = 6.3871(10) Å, b = 8.132(2) Å, c = 12.693(3) Å, α = 89.20(3)°, β = 81.37(3)°, γ = 81.20(3)°, V = 644.2(2) Å3, Z = 2; [Ru(bpy)(CO)3Cl][Cl]·(H5O2)(Cl) (3), Pbcn, a = 20.856(4) Å, b = 13.523(3) Å, c = 13.203(3) Å, V = 3723.7(14) Å3, Z = 8.

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The reductive carbonylation of ruthenium and osmium halides in the presence of cobalt and iron surfaces was studied. In these surface-assisted reactions the metal surface plays an active role in releasing metal ions, which can be used for the in situ synthesis of mixed-metal compounds. A linear, dimetallic, chlorido-bridged, trinuclear complex [Ru 2 Cl 2 (µ-Cl) 4 -(CO) 6 Co(CH 3 CH 2 OH) 2 ] was obtained by the interaction between reducing RuCl 3 and the cobalt surface. In the reaction the RuCl 3 is reduced with carbon monoxide in the presence of a solid cobalt surface in ethanol solution. During the reduction of the RuCl 3 the cobalt surface was simultaneously corroded, releasing cobalt cations. In addition to [Ru 2 Cl 2 (µ-Cl) 4 (CO) 6 Co(CH 3 CH 2 OH) 2 ], the reaction also produced other trinuclear complexes and mononuclear products, such as a bent and linear dimetallic, chlorido-bridged complex with the aqua ligand [Ru 2 Cl 2 (µ-Cl) 4 (CO) 6 Co(H 2 O) 2 ] and ionic

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